COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES British Aerospace (Hawker Siddeley) HS 748 Series Aeroplanes AD/HS 748/9 Auto Feather Micro Switch Operating Levers 1/95 Applicability: All HS 748 series aircraft not incorporating modification 6909. Requirement: Action in accordance with Revision 4 of Jetstream Aircraft Ltd Mandatory SB HS748-76-15. Note: UK CAA AD 0132 refers. Compliance: Within 1000 hours time in service from 5 January 1995. Thereafter, reinspect at intervals not exceeding 1000 hours time in service until modification 6909 has been incorporated. Background: Cracks in the fork end of the levers which actuate the auto feather inhibiting micro switches, located on the engine sub frame, have been reported. In the event of a failed micro switch being followed by an engine failure, propeller auto feathering will not take place.